Hidden deck fastener and method of use

ABSTRACT

A hidden deck fastener for joining adjacent deck boards and securing the boards to an underlying joist includes a biscuit core having an upper face and a lower face, two supporting leg members attached to the lower face, arranged on opposite sides of a central region of the biscuit core and extending downwardly, a screw well located in the central region, the screw well having a central cavity within the upper face and a controlled flash continuous with the lower face, the controlled flash defining the bottom of the well, a ridge defining a central beam extending through a least a lower portion of the screw well, the central beam extending between the leg members through the central region of the biscuit core, and foot members connected to the lower end of the legs, defined by a living hinge groove at the lower end of the legs.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The invention pertains to the field of joining and connecting systems. More particularly, the invention pertains to a fastener for joining adjacent boards and for securing the boards to an underlying support, such as a joist, being particularly well-suited for outdoor platform deck construction.

2. Description of Related Art

Outdoor spaced board platforms, generally referred to as decks, are becoming increasingly popular additions to homes, offices, restaurants and the like. They generally are made from a plurality of elongate, flat laid, closely spaced boards, connected to and supported on their bottom surfaces by framing with spaced joists, stringers, beams or the like, forming a secure floor.

Deck boards traditionally are cut from natural wood or pressure-treated lumber, but have been increasingly manufactured from various composites made from wood and/or other cellulosic materials mixed with various resins, or even plastics and various metals. It is now common for decks to be constructed of hard woods or weatherproof composite materials.

In constructing conventional wood decks, for example, the standard method is to nail directly through the deck boards into the supporting joist members. The problems associated with this method are well known and include: (1) nails backing out with seasonal swelling and shrinkage of the wood, (2) rusting of the nails and staining of the deck boards, (3) wood bruises of the deck boards by hammer marks, and (4) loosening of the boards due to nail pull out.

Unlike conventional treated lumber decks, which typically are nailed or screwed to underlying joists, hardwood deck boards and composite deck boards typically are secured with hidden fasteners or clips to provide a more finished appearance free of visible nail and screw holes. Numerous examples of various fastening devices have been proposed for the purpose of fastening adjacent deck boards to one another and/or securing deck boards to the supporting joists. In some cases, hidden fasteners are inserted into pre-cut slots or biscuit jointer slots formed in the deck boards, and then screwed to the underlying deck joists to hold the deck boards against the joist.

U.S. Pat. No. 6,851,884 discloses an anchoring biscuit device for joining three boards, wherein the biscuit-shaped device includes sidewalls that are not opposite arcs. It includes, (a) a first substantially flat horizontal top element having a generally biscuit-shaped configuration, with opposite sidewalls, at least one of said sidewalls having a flat edge, and at least a portion of said sidewalls being non-parallel with respect to one another; (b) at least one substantially vertical support member attached to the underside of the top element and extending downwardly therefrom for a predetermined length for joinder of two adjacent boards which have been pre-cut with biscuit receiving slots, and, (c) an attachment orifice located at least on the top element for attachment of the anchoring biscuit device to a support board for anchoring and support of the two adjacent boards.

U.S. Pat. No. 6,402,415 discloses an anchoring biscuit device for joining three boards. It includes, (a) a first substantially flat horizontal top element having a generally biscuit-shaped configuration, (b) at least one substantially vertical support member attached to the underside of the top element and extending downwardly therefrom for a predetermined length for joinder of two adjacent boards which have been pre-cut with biscuit receiving slots, and, (c) an attachment orifice located at least on the top element for attachment of the anchoring biscuit device to a support board for anchoring and support of the two adjacent boards.

U.S. Pat. No. 5,738,473 discloses a fastener for securing boards to joists, having first and second sharp, pointed prongs. The first prong has a driving portion for driving the prong at an angle through a first board and a joist thereunder. The second prong extends from the first prong at an angle in the range of about 30 to 60 degrees and acts to secure an adjacent board to the first board. In another aspect, a fastener for securing boards to joists thereunder includes a first member having two parallel sharp, pointed prongs, and a third sharp, pointed prong extending from the first member at an angle in the range of about 35-55 degrees. One of the prongs of the first member is driven into a first board and the other of the prongs is driven into the joist. The third prong secures an adjacent board to the first board.

U.S. Pat. No. 5,027,573 discloses an attachment system, method and connector connection for constructing a structure having supporting members and supported members, as most commonly found in house and patio wood decks, board walks, stair systems, wood benches and trellis systems. The structures are characterized by the apparent absence of nails or other fasteners, however, the structures are securely fastened by nails or screw fasteners in combination with a connector, which is not directly connected to the supporting members.

U.S. Pat. No. 4,925,141 discloses a relatively simple, one nail deck bracket that includes a planar body with prongs extending outwardly from each side thereof for uniformly spacing and interconnecting adjacent planks, and a planar arm extending downwardly from the bottom edge of the body in a plane perpendicular to or otherwise angled with respect to the plane of the body for bearing against one side of the joist, the arm having a hole for receiving a nail for connecting the bracket to the joist. Two arms can be provided at opposite ends of the body for, in effect, straddling the joist.

U.S. Pat. No. 4,620,403 discloses a nailing anchor for use in fixedly attaching a series of parallel wooden boards to a transverse joist. The member has two flat, horizontal tabs each positionable between one of a pair of adjacent boards and the joist. The tabs are fixedly attached to a flat spacer body and extend perpendicularly therefrom in opposite directions. A hole in the one tab allows the anchor to be nailed to the joist. An elongated slot in the spacer body allows the anchor to be toe-nailed through the one adjacent board into the joist. A flat, triangular point depends perpendicularly from an upper edge of the spacer for fastening the one board to the spacer body.

U.S. Pat. Nos. D485,160, D488,373, and D470,039 disclose various ornamental designs for hidden fastening biscuit devices.

U.S. Publication No. 20060107612 discloses an anchoring device comprising a generally horizontal top element having an elongate, generally vertical, collapsible element extending downwardly from the underside thereof, the horizontal top element comprising a metallic plate reinforced plastic.

U.S. Publication No. 20060059822 discloses a deck clip comprising a generally vertically extending leg, and a pair of arms extending from an upper edge of the leg. Each arm is configured for insertion into a slot of a deck board and presents an enlarged lobe. When the deck clip is screwed to a deck joist, the lobes grip the deck boards and hold them tight against the joist. The shape of the lobes increases the gripping force between the lobes and the deck boards as adjacent boards are hammered or otherwise pushed together. The lobes facilitate the gripping of the boards and help maintain the desired gap between adjacent boards for the life of the deck.

Other deck fasteners are known as well. Although there are numerous known devices that are intended to aid in fastening adjacent deck boards to one another and/or securing deck boards to the supporting joists, unfortunately, prior art deck clips suffer from several problems, which limit their utility. For example, many prior art deck clips don't provide substantial holding force, resulting in loose deck boards. Many prior art deck clips also are difficult to install or do not effectively grip the deck boards, often causing the boards to shift. Thus, there is a need in the art for an improved hidden deck fastener that is easy to install and effectively grips the deck boards and secures them to the joists.

SUMMARY OF THE INVENTION

The present invention provides a fastener for fastening adjacent deck boards to one another and securing the deck boards to the supporting joist. Briefly stated, the apparatus according to the invention provides a hidden deck fastener including a biscuit core having an upper face and a lower face, two supporting leg members attached to the lower face, arranged on opposite sides of a central region of the biscuit core and extending downwardly, a screw well located in the central region, the screw well having a central cavity within the upper face and a controlled flash continuous with the lower face, the controlled flash defining the bottom of the well.

In the preferred embodiment, the invention provides a hidden deck fastener including a biscuit core having an upper face and a lower face, two supporting leg members attached to the lower face, arranged on opposite sides of a central region of the biscuit core and extending downwardly, a screw well located in the central region, the screw well having a central cavity within the upper face and a controlled flash continuous with the lower face, the controlled flash defining the bottom of the well, a ridge defining a central beam extending through a least a lower portion of the screw well, the central beam extending between the leg members through the central region of the biscuit core, and foot members connected to the lower end of the legs, defined by a living hinge groove at the lower end of the legs.

The invention provides an improved fastener for fastening adjacent deck boards to one another and securing the deck boards to the supporting joist, that is stronger, easier to install, more effective at securing boards to an underlying joist, and more effective at preventing relative movement between adjacent boards. These and other features and advantages will become readily apparent from the following detailed description, which should be read in conjunction with the accompanying drawing figures.

BRIEF DESCRIPTION OF THE DRAWING

FIG. 1 shows a perspective view of a deck fastener according to an embodiment of the present invention.

FIG. 2 shows a top view of a deck fastener according to an embodiment of the present invention.

FIG. 3 shows a side view of a deck fastener according to an embodiment of the present invention.

FIG. 4 shows a front side elevation view of a deck fastener according to an embodiment of the present invention.

FIG. 5 shows a side view of a deck fastener with folding legs, according to an embodiment of the present invention.

FIG. 6 shows a bottom side view of a deck fastener according to an embodiment of the present invention.

FIG. 7 shows a side view of nail placement into a deck fastener according to an embodiment of the present invention.

FIG. 8 shows deck boards fastened using a deck fastener according to an embodiment of the present invention.

DETAILED DESCRIPTION OF THE INVENTION

The following description relates to certain preferred embodiments of a hidden deck fastener for fastening adjacent deck boards to one another and securing the deck boards to the supporting joist. It is understood that numerous variations and modifications, other than those specifically indicated herein, will be readily apparent to those of sufficient skill in the art. In addition, certain terms are used throughout the discussion in order to provide a convenient frame of reference with regard to the accompanying drawings, such as “upper”, “lower”, “top”, “bottom”, “side”, and the like. Such terms are not intended to be specifically limiting of the invention, except where so indicated in the claims. Obviously, numerous modifications and variations of the present invention are possible in light of the teachings herein. It is therefore understood that within the scope of the appended claims, the invention may be practiced otherwise than as specifically described herein.

The present invention solves various problems and provides a distinct advance in the art of deck fasteners. More particularly, the present invention provides an improved fastener for fastening adjacent deck boards to one another and securing the deck boards to the supporting joist, that is stronger, easier to install, more effective at securing boards to an underlying joist, and more effective at preventing relative movement between adjacent boards. The apparatus according to the invention provides a hidden deck fastener including a biscuit core having an upper face and a lower face, two supporting leg members attached to the lower face and extending downwardly therefrom, arranged on opposite sides of a central region of the biscuit core, a screw well located in the central region, the screw well having a central cavity within the upper face and a controlled flash continuous with the lower face, the controlled flash defining the bottom of the well.

In the preferred embodiment, the invention provides a hidden deck fastener including a biscuit core having an upper face and a lower face, two supporting leg members attached to the lower face and extending downwardly therefrom, arranged on opposite sides of a central region of the biscuit core, a screw well located in the central region, the screw well having a central cavity within the upper face and a controlled flash continuous with the lower face, the controlled flash defining the bottom of the well, a ridge defining a central beam extending through a least a lower portion of the screw well, the central beam extending between the leg members through the central region of the biscuit core, and foot members connected to the lower end of the legs, defined by a living hinge groove at the lower end of the legs.

Referring now to FIGS. 1-6, a deck fastener 100 constructed in accordance with one embodiment of the present invention broadly comprises a biscuit core 10 having an upper face 205 and a lower face 210, and two supporting leg members 20 a,b perpendicular to the plane of the biscuit core 10, extending downwardly from the lower face 210 thereof. The supporting leg members 20 a,b are arranged on opposite sides of the central region of the biscuit core, leaving space for a nail or screw to pass between the legs into a joist or support board. The supporting leg members 20 a,b have a predetermined height, so as to rest on a joist in such a way as to establish biscuit core 10 at a predetermined height from the joist for attachment of two adjacent boards thereto, which have corresponding pre-cut biscuit slots.

The upper surface of the biscuit core also includes a screw well 30 located on center. This enables the user to nail or screw the deck fastener 100 into a joist, as more fully described in conjunction with FIGS. 7-8. The screw well 30 is located within the central region of the biscuit core 10, the bottom of the well being defined by controlled flash 40, which forms a thin layer of material over the bottom of the central cavity 30, thus defining the bottom of the well. The central cavity of screw well 30 marks the location for the screw, but the cavity does not extend through the biscuit core 10. Rather, the controlled flash 40 at the bottom provides a thin (preferably 0.025″ thick) layer of material covering the bottom of the screw well. The controlled flash forms a continuous smooth surface with the lower face of the biscuit core, such that there are no holes penetrating through the biscuit core. The controlled flash thus covers the bottom of the screw well, but allows the screw to penetrate.

In the preferred embodiment, a central beam 80 runs through the center at the bottom of the screw well, providing additional structure to the screw well. Central beam 80 extends through the plane of the biscuit core 10 between the legs 20 a,b through the screw well 30, thus providing additional integrity to the installation and aiding to prevent screw pull-out. Preferably the central beam 80 is formed as a triangular ridge, on which the screw shank rests when set at a 45 degree angle. Preferably, the central cavity of screw well 30 also has a beveled edge 70 and is formed as an elongated oval, to facilitate the screws better. The screw is placed into the screw well and driven through the controlled flash at the bottom of the well. The center beam provides added support at the base of the screw, which helps to prevent pull-outs and shifting of the deck boards.

Additionally, in the preferred embodiment, foot members 60 a,b, defined by living hinge 50, are activated upon pushing the fastener 100 down against a joist. The deck fastener is inserted into the slot or groove and centered on the joist. When the deck fastener is inserted into the slot and pushed down against the joist, the living hinge is activated and the feet move into place. The tapered foot slides under the deck board, lifting the deck board off the joist, thereby allowing air to circulate between the deck boards and the joists. This helps to prevent moisture accumulation and premature decay. The fastener is screwed to a deck joist to hold the deck board tight against the joist, and the adjoining board is fitted over the biscuit core and up against the first board, repeating the steps as necessary to extend the structure.

The biscuit core is configured to fit into a pre-milled slot or groove, or a biscuit-cutter machined slot formed in the edges of the deck boards. Each leg is configured to hold the biscuit core up and in position, while also providing consistent spacing between adjacent boards. When the deck fastener is pushed down against the joist, the feet are activated and each foot points in the opposite direction, sliding under the adjacent deck boards. In the example shown herein, the biscuit core is in the form of a rectangle having rounded corners, however, this shape is not critical to the invention and other shapes are suitable. The deck fastener can be made from practically any material, but preferably is made from a thermoplastic material, such as polypropylene or polyethylene (more preferably HDPE) by injection molding. Other suitable materials may include wood or wood composites, metal alloys or composites, styrene polymers and copolymers, ABS, acrylics, cellulosics, vinyls, nylons, polycarbonate, PVC and various fluorocarbon materials.

EXAMPLE 1

An example of the present invention was manufactured from high density polyethylene (HDPE) using a sixteen (16) cavity mold in a 150 ton Engel injection molding machine. The example is essentially as shown in FIGS. 1-8. In this example, the biscuit core 10 is about ⅛″ thick, and the supporting legs 20 a,b are about 3/32″ thick and ⅛″ apart. The feet 60 a,b are defined by living hinges 50 a,b at the lower end of the legs, and are activated by pushing the deck fastener 100 down against the joist. With the living hinged feet activated, the distance between the lower face of the biscuit core and the top side of the feet is ⅜″. In this example, the controlled flash is 0.025″ thick and the center beam is 0.05″ tall (at center of ridge). The deck fastener can be used with pre-grooved deck boards, or a ⅛″ router bit or a #20 biscuit cutter can be used to cut the slots, where needed. When cutting the slots, the slot should be cut in each board ⅜″ from the bottom surface. The deck fastener preferably is secured with a #72¼″ stainless steel screw on a 45 degree angle to the joist, as shown in FIGS. 7-8. Pre-drilling the hole with a ⅛″ drill is recommended. 

1. A fastening device, comprising: a) a biscuit core having an upper face and a lower face; b) two supporting leg members extending downwardly from the lower face, arranged on opposite sides of a central region of the biscuit core; c) a screw well located in the central region, the screw well comprising a central cavity within the upper face and a controlled flash continuous with the lower face, the controlled flash defining the bottom of the well.
 2. The device of claim 1, further comprising: d) a ridge defining a central beam extending through a least a lower portion of the screw well, the central beam extending between the leg members through the central region of the biscuit core.
 3. The device of claim 2, further comprising: e) a foot member connected to a lower end of at least one of the leg members, the foot member being defined by a living hinge groove formed within the lower end of the leg member.
 4. The device of claim 1, wherein the central cavity of the screw well has a beveled edge.
 5. The device of claim 4, wherein the central cavity of the screw well is non-circular and elongated.
 6. The device of claim 1, wherein the biscuit core and the supporting leg members are unitarily formed.
 7. The device of claim 6, wherein the device comprises a polyolefin or a thermoplastic material.
 8. The device of claim 7, wherein the material is polypropylene, polyethylene or high density polyethylene.
 9. The device of claim 8, wherein the device is manufactured by injection molding.
 10. A fastening device, comprising: a) a biscuit core having an upper face and a lower face; b) two supporting leg members extending downwardly from the lower face, arranged on opposite sides of a central region of the biscuit core; c) a screw well located in the central region, the screw well comprising a central cavity within the upper face and a controlled flash continuous with the lower face, the controlled flash defining the bottom of the well; d) a ridge defining a central beam extending through a least a lower portion of the screw well, the central beam extending between the leg members through the central region of the biscuit core; and e) a foot member connected to a lower end of at least one of the leg members, the foot member being defined by a living hinge groove formed within the lower end of the leg member.
 11. The device of claim 10, wherein the central cavity of the screw well has a beveled edge.
 12. The device of claim 10, wherein the central cavity of the screw well is non-circular and elongated.
 13. The device of claim 10, wherein the biscuit core and the supporting leg members are unitarily formed.
 14. The device of claim 13, wherein the device comprises a polyolefin or a thermoplastic material.
 15. The device of claim 14, wherein the material is polypropylene, polyethylene or high density polyethylene.
 16. The device of claim 15, wherein the device is manufactured by injection molding.
 17. A method for joining boards, comprising the steps of: a) providing one or more two boards to be joined and a supporting joist therefore; b) providing a fastener according to claim 1; and c) inserting the fastener into a receiving slot of the board and driving a nail or screw through the controlled flash and into the joist. 